How long do you think it will be before the team with the worst engine seeks a dispensation from the FIA (bowing before King Max and groveling like a smurf) for some performance enhancing modification? How long will it be before the teams accuse their rivals of making secret changes to their engines? Who will be the first team to be accused of cheating? All it will take is some team to "improve" a bit more than they "should" before the accusations fly.
And just how many teams will shut down their engine research depts? My bet is that they will continue to run unabated all working on "fuel economy" (a politically correct cover story if there ever was one), on management systems/emissions, on lubricants/metalurgy for "reliability" or they will even claim to be working on their 2011 engines.
And finally, how long will it be before the freeze is found to be unworkable just like the traction control prohibition? Just another bad idea foisted upon the teams by Mad Max the tyranical evil dictator.